Question
How many distinct 5 digit numbers can be formed using the digits 3, 2, 3, 2, 4, 5.

Answer

5 digit numbers are to be formed from 2, 3, 2, 3, 4, 5. Case I: Numbers formed from 2, 2, 3, 4, 5 OR 2, 3, 3, 4, 5

Number of such numbers $=\frac{5 !}{2 !}+\frac{5 !}{2 !}=5 !=120$

Case II: Numbers are formed from 2, 2, 3, 3 and any one of 4 or 5

Number of such numbers $=\frac{5 !}{2 ! 2 !}+\frac{5 !}{2 ! 2 !}=60$

Required number of numbers = 120 + 60 = 180

Need a full question paper?

Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.

Start Generating Free